Main Content

Research

Deception

Psychological basis: We investigate the psychological mechanisms underlying deception and lying. On one hand, we explore the cognitive processes involved in lying, including the mental abilities required for effective deception. Additionally, we aim to understand the emotional processes at play during deception. We are investigating these questions in a DFG-funded Emmy Noether project "What lies beneath lies? Integrating cognitive and emotional experimental approaches to deception". Further examples can be found in the following publications:

  • Suchotzki K., Verschuere, B., Van Bockstaele, B., Ben-Shakhar, G., & Crombez, G. (2017). Lying Takes Time: A Meta-Analysis on Reaction Time Measures of Deception. Psychological Bulletin, 143(4), 428-453. https://doi.org/10.1037/bul0000087
  • Suchotzki K., Verschuere, B., Peth, J., Crombez, G., & Gamer, M. (2015). Manipulating item proportion and deception reveals crucial dissociation between behavioral, autonomic, and neural indices of concealed information. Human Brain Mapping, 36(2), 427-439. https://doi.org/10.1002/hbm.22637
  • Suchotzki K., Crombez, G., Debey, E., Van Oorsouw, K., & Verschuere, B. (2015). In Vino Veritas? Alcohol, Response Inhibition and Lying. Alcohol and Alcoholism, 50(1), 74-81. https://doi.org/10.1093/alcalc/agu079

Moderating factors: We are also interested in factors that potentially influence the psychological processes involved in lying. For instance, we look at how lying in a foreign language affects cognitive effort and the role of motivation or punishment:

  • Suchotzki K., & Gamer, M. (2019). Effect of Negative Motivation on the Behavioral and Autonomic Correlates of Deception. Psychophysiology, 56(1), e13284. https://doi.org/10.1111/psyp.13284
  • Suchotzki K. & Gamer, M. (2018). The language of lies: Behavioral and autonomic costs of lying in a native compared to a foreign language. Journal of Experimental Psychology: General, 147(5), 734-746. https://doi.org/10.1037/xge0000437

Lie detection: We critically assess existing lie detection methods, such as attempts to detect lies via behavioral cues or with the so-called polygraph. Many of these methods lack empirical evidence, meaning they are not based on scientific theories and have not proven effective in empirical studies. Unfortunately, this also applies to lie detection using newer technologies, as discussed in in this article:

Concealed Information

Concealed information detection serves as an alternative to traditional lie detection. Rather than determining whether someone is lying, this method aims to ascertain whether the individual possesses relevant knowledge, such as incriminating crime details. This procedure, known as the Concealed Information Test (CIT), is grounded in empirically validated psychological theory. Meta-analyses demonstrate its high classification accuracy in laboratory research. In our studies, we further investigate the theoretical basis of the test and develop more ecologically valid experimental designs to assess whether its high performance extends to realistic conditions. Examples can be found in the following publications:

  • Suchotzki, K., Verschuere, B., & Gamer, M. (2021). How Vulnerable is the Reaction Time Concealed Information Test to Faking? Journal of Applied Research in Memory and Cognition, 10(2), 268-277. https://doi.org/10.1016/j.jarmac.2020.10.003
  • Suchotzki, K., May, H., & Gamer, M. (2020). No effect of moderate alcohol intake on the detection of concealed identity information in the laboratory. Scientific Reports, 10/(1), 1-7. https://doi.org/10.1038/s41598-020-76811-x
  • Suchotzki K., Kakavand, A., & Gamer, M. (2018). Validity of the Reaction Time Concealed Information Test in a Prison Sample. Frontiers in Psychiatry, 9, 745. https://doi.org/10.3389/fpsyt.2018.00745

Credibility assessment of witness testimonies in Germany

In Germany, psychological experts routinely assess the credibility of witness statements as part of legal psychological assessments. This process involves the so-called criteria-based content analysis (CBCA), in which one examines the extent to which statements exhibit content-related quality characteristics expected in statements based on actual experiences (e.g., as a crime-victim) in contrast to fabricated statements. In ongoing research projects, we investigate the validity of this method under conditions closely resembling its real-world application. Additionally, we explore how experts implement this method in practice.

Eyewitnesses

Misidentifications of suspects are one of the most common causes of wrongful convictions in criminal proceedings. As the reliable assessment of correct and incorrect identifications in the context of real-life lineups remains to be a major difficulty, our research focuses on the relationship between individual characteristics as well as situational and procedural factors and eyewitness accuracy.

Methods

We employ diverse methods depending on the research question. These range from text analyses for coding witness statement content, to reaction times in experimental paradigms as a measure of cognitive effort during lying, to physiological and neuronal measures aimed at capturing individual psychological mechanisms. Additionally, we utilize virtual reality to enhance the realism of experimental scenarios while maintaining experimental control.